1. Technical Field
The present invention relates to a facsimile system having a paper saving function, and more particularly relates to a method for saving print paper in a facsimile system by overlapping a transmit terminal identification (TTI) with real document data.
2. Related Art
A conventional facsimile system has a capability of sending information such as transmit terminal identification (TTI) for identifying the terminal from which the facsimile transmission is made, to other communication terminals according to a pre-transmission procedure. By performing the pre-transmission procedure, TTI information is added at the head or upper end portion of the page to be transmitted after conversion to an image formation. In some facsimile systems such as disclosed in U.S. Pat. No. 5,021,889 for Facsimile Apparatus issued to Yamamoto, the TTI information is made only to restricted communication terminals which are registered in a memory in order to prevent undesirable transmission of the TTI information to unwanted communication terminals.
Generally, in such facsimile systems, if the length of the content of a received document exceeds the content-allowable print length of each individual sheet of print paper not including the upper and lower margins and the TTI region, the remaining content of the received document that may not be included in the same sheet would be lost or printed on a next sheet of the print paper. If the remaining content of the received document is printed on the next sheet without completely filling up the page, it is cost prohibitive notwithstanding the user inconvenience in the maintenance of the document. Of course, if the facsimile systems are those that use a print paper in a paper roll, there is no danger to lose a part of the content of the transmitted document, but the cost prohibition remains.
Recent efforts in the art to conserve the print paper in the facsimile system are disclosed, for example, in U.S. Pat. No. 5,428,459 for Facsimile Apparatus For Minimizing Printing Of White Data At End Of Page issued to Asai, U.S. Pat. No. 5,455,686 for Facsimile Apparatus With Paper Saving Function issued to Nagano et al., and U.S. Pat. No. 5,493,421 for Facsimile Apparatus issued to Uetama et al. For example, Asai '459 discloses a facsimile system for minimizing printing white data at end of the page. Nagano et al. '686 discloses a facsimile system for saving consumption of print paper by the contraction-printing in the longitudinal direction of the print paper. Uetama et al. '421 seeks to print the original while omitting the unrequited data portion such as the margin of the original in order to conserve print paper. While the conventional facsimile system has several paper saving functions, I have noted that farther improvement to conserve print paper can be still contemplated.